Add donut chart breakdown example

Task-number: PYSIDE-738
Change-Id: I9b75a87615ef5888d98e21c8429f425a05e3a08c
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Christian Tismer <tismer@stackless.com>

1 files changed, 181 insertions, 0 deletions

diff --git a/examples/charts/donutbreakdown.py b/examples/charts/donutbreakdown.py
new file mode 100644
index 000000000..28a48b8ac
--- /dev/null
+++ b/examples/charts/donutbreakdown.py
@@ -0,0 +1,181 @@
+#############################################################################
+##
+## Copyright (C) 2018 The Qt Company Ltd.
+## Contact: http://www.qt.io/licensing/
+##
+## This file is part of the Qt for Python examples of the Qt Toolkit.
+##
+## $QT_BEGIN_LICENSE:BSD$
+## You may use this file under the terms of the BSD license as follows:
+##
+## "Redistribution and use in source and binary forms, with or without
+## modification, are permitted provided that the following conditions are
+## met:
+##   * Redistributions of source code must retain the above copyright
+##     notice, this list of conditions and the following disclaimer.
+##   * Redistributions in binary form must reproduce the above copyright
+##     notice, this list of conditions and the following disclaimer in
+##     the documentation and/or other materials provided with the
+##     distribution.
+##   * Neither the name of The Qt Company Ltd nor the names of its
+##     contributors may be used to endorse or promote products derived
+##     from this software without specific prior written permission.
+##
+##
+## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+## "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+## LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+## A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+## OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+## SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+## LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+## DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+## THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+## (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+##
+## $QT_END_LICENSE$
+##
+#############################################################################
+
+"""PySide2 port of the Donut Chart Breakdown example from Qt v5.x"""
+
+
+import sys
+from PySide2.QtCore import Qt
+from PySide2.QtGui import QColor, QFont, QPainter
+from PySide2.QtWidgets import QApplication, QMainWindow
+from PySide2.QtCharts import QtCharts
+
+class MainSlice(QtCharts.QPieSlice):
+    def __init__(self, breakdown_series, parent=None):
+        super(MainSlice, self).__init__(parent)
+
+        self.breakdown_series = breakdown_series
+        self.name = None
+
+        self.percentageChanged.connect(self.update_label)
+
+    def get_breakdown_series(self):
+        return self.breakdown_series
+
+    def setName(self, name):
+        self.name = name
+
+    def name(self):
+        return self.name
+
+    def update_label(self):
+        self.setLabel("{} {:.2f}%".format(self.name,
+            self.percentage() * 100))
+
+
+class DonutBreakdownChart(QtCharts.QChart):
+    def __init__(self, parent=None):
+        super(DonutBreakdownChart, self).__init__(QtCharts.QChart.ChartTypeCartesian, parent, Qt.WindowFlags())
+        self.main_series = QtCharts.QPieSeries()
+        self.main_series.setPieSize(0.7)
+        self.addSeries(self.main_series)
+
+    def add_breakdown_series(self, breakdown_series, color):
+        font = QFont("Arial", 8)
+
+        # add breakdown series as a slice to center pie
+        main_slice = MainSlice(breakdown_series)
+        main_slice.setName(breakdown_series.name())
+        main_slice.setValue(breakdown_series.sum())
+        self.main_series.append(main_slice)
+
+        # customize the slice
+        main_slice.setBrush(color)
+        main_slice.setLabelVisible()
+        main_slice.setLabelColor(Qt.white)
+        main_slice.setLabelPosition(QtCharts.QPieSlice.LabelInsideHorizontal)
+        main_slice.setLabelFont(font)
+
+        # position and customize the breakdown series
+        breakdown_series.setPieSize(0.8)
+        breakdown_series.setHoleSize(0.7)
+        breakdown_series.setLabelsVisible()
+
+        for pie_slice in breakdown_series.slices():
+            color = QColor(color).lighter(115)
+            pie_slice.setBrush(color)
+            pie_slice.setLabelFont(font)
+
+        # add the series to the chart
+        self.addSeries(breakdown_series)
+
+        # recalculate breakdown donut segments
+        self.recalculate_angles()
+
+        # update customize legend markers
+        self.update_legend_markers()
+
+    def recalculate_angles(self):
+        angle = 0
+        slices = self.main_series.slices();
+        for pie_slice in slices:
+            breakdown_series = pie_slice.get_breakdown_series()
+            breakdown_series.setPieStartAngle(angle)
+            angle += pie_slice.percentage() * 360.0 # full pie is 360.0
+            breakdown_series.setPieEndAngle(angle)
+
+    def update_legend_markers(self):
+        # go through all markers
+        for series in self.series():
+            markers = self.legend().markers(series)
+            for marker in markers:
+                if series == self.main_series:
+                    # hide markers from main series
+                    marker.setVisible(False)
+                else:
+                    # modify markers from breakdown series
+                    marker.setLabel("{} {:.2f}%".format(
+                        marker.slice().label(),
+                        marker.slice().percentage() * 100, 0))
+                    marker.setFont(QFont("Arial", 8))
+
+if __name__ == "__main__":
+    app = QApplication(sys.argv)
+    # Graph is based on data of:
+    #    'Total consumption of energy increased by 10 per cent in 2010'
+    # Statistics Finland, 13 December 2011
+    # http://www.stat.fi/til/ekul/2010/ekul_2010_2011-12-13_tie_001_en.html
+    series1 = QtCharts.QPieSeries()
+    series1.setName("Fossil fuels")
+    series1.append("Oil", 353295)
+    series1.append("Coal", 188500)
+    series1.append("Natural gas", 148680)
+    series1.append("Peat", 94545)
+
+    series2 = QtCharts.QPieSeries()
+    series2.setName("Renewables")
+    series2.append("Wood fuels", 319663)
+    series2.append("Hydro power", 45875)
+    series2.append("Wind power", 1060)
+
+    series3 = QtCharts.QPieSeries()
+    series3.setName("Others")
+    series3.append("Nuclear energy", 238789)
+    series3.append("Import energy", 37802)
+    series3.append("Other", 32441)
+
+    donut_breakdown = DonutBreakdownChart()
+    donut_breakdown.setAnimationOptions(QtCharts.QChart.AllAnimations)
+    donut_breakdown.setTitle("Total consumption of energy in Finland 2010")
+    donut_breakdown.legend().setAlignment(Qt.AlignRight)
+    donut_breakdown.add_breakdown_series(series1, Qt.red)
+    donut_breakdown.add_breakdown_series(series2, Qt.darkGreen)
+    donut_breakdown.add_breakdown_series(series3, Qt.darkBlue)
+
+    window = QMainWindow()
+    chart_view = QtCharts.QChartView(donut_breakdown)
+    chart_view.setRenderHint(QPainter.Antialiasing)
+    window.setCentralWidget(chart_view)
+    available_geometry = app.desktop().availableGeometry(window)
+    size = available_geometry.height() * 0.75
+    window.resize(size, size * 0.8)
+    window.show()
+
+    sys.exit(app.exec_())